Metal ring for positioning the cylinder sleeve in the cylinder block of a liquid-cooled piston type internal combustion engine



June 25, 1968 o. HERSCHMANN ET AL 3,389,693

METAL RING FOR POSITIONING E INDER EVE IN THE CYLINDER BLOCK A LI D- LED PI N TYPE INTERN COMBUSTION ENGINE Filed Aug. 12, 1966 FIG. I

/ZIIIIIIIIA IIIAVI/lll/ll' INVENTORS.

OTTO HERSCHMANN HERBERT DEUTSCHMANN a! 5 BY ATTOR EYS.

United States Patent 3,389,693 METAL RING FOR POSITIONING THE CYLIN- DER SLEEVE IN THE CYLINDER BLOCK OF A LlQUlD-COOLED PISTON TYPE INTERNAL COMBUSTION ENGINE Otto Herschmann, Fellbach, Wurttemburg, and Herbert Deutschmann, Stuttgart-Bad Cannstatt, Germany, assignors to Daimler-Benz Aktiengesellschaft, Stuttgart- Unterturkheim, Germany Filed Aug. 12, 1966, Ser. No. 572,091 Claims priority, application Germany, Aug. 12, 1965,

14 Claims. (Cl: 123-41154 The present invention relates to a liquid-cooled piston internal combustion engine, and more particularly to a metal ring for liquid-cooled piston internal combustion engines having a cylinder-crankcase of light metal.

With liquid-cooled piston internal combustion engines having a cylinder-crankcase of light metal, the ringshaped support at the inner side of the cylinder cooling jacket serving for the collar of the cylinder liner is particularly strongly loaded and stressed. It has been found that particularly at this place damages due to cavitation and corrosion may occur in the course of time. Added thereto are the alternating loads or stresses, to which is exposed the support during operation, whereby, for the most part, local loads or stresses are superposed on these alternating loads which stem from deformations of the liner and the collar thereof. These deformations may also result from non-uniform heating of the cylinder liner. Another cause of the deformations are the vibrations which are caused by the differing sliding pressures of the piston. Also small form defects produced during the manufacture have the same effects. The stress peaks thus produced may lead to the possibility that the support is lowered slightly, is torn or is damaged otherwise.

It is the aim of the present invention to avoid such damages in that a metal ring is arranged between the ring-shaped support surfaces at the cylinder cooling jacket and at the collar of the cylinder liner. However, it is also possible within the scope of the present invention to install only subsequently such a metal ring during repairs of these damages.

The use of such a ring for repair purposes is known. For that purpose, the support is turned corresponding to the shape of the repair ring and the latter is secured in the housing by pressing-in, shrinking or glueing-in. L- and Z-shaped cross sections or profiles are normally used as ring" cross sections in the prior art. With the intention to weaken the support as little as possible, these profiles or cross sections are kept very thin.

In contradistinction thereto, the ring according to the present invention has essentially a rectangular cross section whose height is related to its width in the ratio of about 2.5 :1 to about 1:1. Furthermore, the width of the ringcorresponds at least to the width of the support surfaces at the cylinder cooling jacket and at a collar of the cylinder liner.

The sturdy and solid rectangular cross section of the ring has the purpose together with the wide support surfaces to transmit the alternating and unilaterally acting loads uniformly distributed to the light-metal case. Excessive loads of the support, which might lead to damages, are thereby eliminated.

A further advantage with respect to the known rings results from the high moment of resistance or section modulus of the ring which as a result thereof with the same pressing or shrinking stress, is seated securely in the housing with a high radial stress. If one additionally glues-in the ring, then the large glueing surface of the ring according to the present invention produces a particularly good connection. As a result of the high rigidity important if, with 3,389,693 Patented June 25, 1968 ice of the ring, deformations are avoided so that a tearing of the glue layer need not be feared.

The good seating of the ring in the housing relieves far-reachingly the ring-shaped support at the cylinder cooling jacket. It is therefore also possible to constitute the support of weaker construction. This is particularly subsequent installation of the ring, a portionof the support has to be turned or machined.

According to a further feature and development of the present invention, the inner diameter of the ring becomes larger in the direction toward the lower end face opposite the support at the cylinder cooling jacket whereas the inner diameter of the ring remains constant at least within the area of its upper end face opposite the cylinder liner. The portion of the cylinder liner, about which flows the cooling liquid, is thereby enlarged in a particularly thermally loaded section thereof and therewith the cooling is considerably improved.

It is also possible that the ring at its upper end face includes according to the present invention, a collar whose outer diameter is the same as the remaining ring and whose inner diameter is larger than the outer diameter of the collar of the cylinder liner. As a result thereof, the seating surface of the ring is enlarged or widened in an advantageous manner and the sealing is improved.

According to the present invention, the danger of cavitation and of corrosion is effectively counteracted in that the ring is made of austenitic steel which is particularly resistant against this type of harmful influences.

Accordingly, it is an object of the present invention to provide an internal combustion engine, and more particularly a liquid-cooled piston internal combustion engine, which avoids the aforementioned drawbacks and shortcomings encountered with the prior art constructions.

It is another object of the present invention to provide a metal ring for liquid-cooled piston internal combustion engines which effectively prevents tearing or damaging of the support surfaces.

A further object of the present invention resides in a metal ring for liquid-cooled piston internal combustion engines which is so constructed and arranged that it may be readily installed into an existing engine when repairs require an exchange of such a ring.

A further object of the present invention resides in a metal ring of the type described above for liquid-cooled piston internal combustion engines which evenly distributes the alternating and unilateral loads to the light metal housing of the engine.

Another object of the present invention is to provide a metal ring interposed between the cylinder liner and support surface of a liquid-cooled piston internal combustion engine which eliminates damage of the support surfaces as a result of excessive loads.

A further object of the present invention resides in a metallic ring of the type described above which not only permits the attainment of a particularly good connection with the support surface but also reduces the danger of damage to such connection as a result of deformation.

Still another object of the present invention resides in a metallic ring of the type described above for use in liquid-cooled piston internal combustion engines which permits a considerable improvement in the cooling of the engine while eliminating substantially the danger due to cavitation and corrosion.

These and further objects, features, and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, several embodiments in accordance with the present invention, and wherein:

FIGURE 1 is a cross-sectional view through an internal combustion engine provided with a ring having a square cross section in accordance with the present invention;

FIGURE 2 is a partial cross-sectional view, similar to FIGURE 1, of a modified embodiment of a ring according to the present invention having a modified rectangular cross section; and

FIGURE 3 is a partial cross-sectional view, similar to FIGURE 2, of a ring in accordance with the present invention having a modified rectangular cross section and a collar.

Referring now to the drawing wherein like reference numerals are used throughout the various views to designate like parts, reference numeral 11 designates in all views a cylinder-crankcase made of light-weight metal of a liquid-cooled piston internal combustion engine into which is inserted a conventional cylinder liner 112. A portion of the cylinder-crankcase 11 forms the cylinder 13 which delimits in the outward direction the cooling space 14 surrounding the cylinder liner 12. Sealing rings 15 and 16 seal the cooling space 14 with respect to the lower part of the cylinder-crankcase 11. A support 17 with a ringshaped support surface 18 extends peripherally in the upper portion of the cylinder cooling jacket -13. A shrunkon steel ring 20 is supported with its lower end face 19 on the abutment surface 18, which steel ring 24} has a square cross section. The support or abutment surface 22 of a collar 23 of the cylinder liner 12 rests on the upper end face 21 of the ring 20.

The ring 24 illustrated in FIGURE 2 has an essentially rectangular cross section. Its inner diameter is essentially constant within the area of its upper end face 25 opposite the collar 23 at the cylinder liner 12. The inner diameter, however, becomes larger in the direction toward the lower end face 26 opposite the ing jacket 13. The ring 24 is made of austenitic steel and at the cylinder liner 12. The ring 28 is shrunk into the cylinder-crankcase 11 and is additionally bonded or glued therein by any suitable known bonding material.

The ring 28 of FIGURE 3 may also be made of any suitable material such as austenitic steel.

While we have shown and that the ring has approximately a rectangular cross section whose height is related to its width at the ratio of about 2.5 :l to 1:1, and whose width corresponds to at least the width of the abutment surfaces at one of the two parts consisting of the cylinder cooling jacket and the collar at the cylinder liner.

2. A metal ring according to claim 1, wherein the inner diameter thereof becomes larger in the direction toward the lower end face opposite the support at the cylinder cooling jacket whereas at least within the area of the upper end face opposite the collar of the cylinder liner, the inner diameter remains substantially constant.

3. A ring according to claim 2, which further comprises a collar at the upper end face thereof, the inner diameter of the collar of the metal ring being larger than the outer diameter of the collar of the cylinder liner.

4. A ring according to claim 3, essentially consisting of austenitic steel.

5. A ring according to claim 1, which further comprises a collar at the upper end face thereof, the inner diameter of the collar of the metal ring being larger than the outer diameter of the collar of the cylinder liner.

6. A ring according to claim 1, essentially consisting of austenitic steel.

7. In a liquid-cooled piston internal combustion engine, a cylinder-crankcase forming a cooling jacket,

liner having a collar, said cooling jacket being provided on the inside thereof means, a metal ring arranged between the abutment surface means at the cooling jacket and at the collar of the cylinder liner, and said ring having approximately a rectangular cross section whose height is related to its width at the ratio of about 2.5:1 to 1:1.

8. The combination according to claim 7, wherein the width of said ring is at least as large as the width of the abutment surface means at the cooling jacket.

9. The combination according claim 7, wherein the width of said ring is at least as large as the width of the abutment surface means at the collar of said liner.

10. The combination according to claim 7, wherein the width of said ring is at least as large as the width of each of said abutment surface means.

11. The combination according to claim 7, wherein the inner diameter of the ring increases in the direction toward the abutment surface means at the cylinder cooling jacket whereas at least within the area of the abutment surface means at the collar of the cylinder liner, the inner diameter remains substantially constant.

12. The combination according to claim 7, wherein the ring includes a collar at the upper end face thereof, whose inner diameter is larger than the outer diameter of the collar of the cylinder liner.

'13. The combination according to claim 11, essentially consisting of austenitic steel.

14. The combination according to claim 7, essentially consisting of austenitic steel.

References Cited UNITED STATES PATENTS JULIUS E. WEST, Primary Examiner. 

7. IN A LIQUID-COOLED PISTON INTERNAL COMBUSTION ENGINE, A CYLINDER-CRANKCASE FORMING A COOLING JACKET, A CYLINDER LINER HAVING A COLLAR, SAID COOLING JACKET BEING PROVIDED ON THE INSIDE THEREOF WITH RING-SHAPED ABUTMENT SURFACE MEANS, SAID CYLINDER LINER BEING PROVIDED ALSO WITH RINGSHAPED ABUTMENT SURFACE MEANS, A METAL RING ARRANGED BETWEEN THE ABUTMENT SURFACE MEANS AT THE COOLING JACKET AND AT THE COLLAR OF THE CYLINDER LINER, AND SAID RING HAVING APPROXIMATELY A RECTANGULAR CROSS SECTION WHOSE HEIGHT IS RELATED TO ITS WIDTH AT THE RATIO OF ABOUT 2.5:1 TO 1:1. 